THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

[18:00:38]

WOLF BLITZER, CNN ANCHOR: Happening now: rules of war. The U.S. and Russia sign a deal to avoid disaster after their warplanes come dangerously close to crashing in the skies over Syria. Why are the specifics being kept a secret?

Spy chief exposed. Alleged cyber-criminals tell CNN they're ready to go public with information stolen from the CIA director's private e-mail. Are the feds any closer to nabbing the hackers?

Fugitive spotted. We have new details about the manhunt for the drug lord known as El Chapo after his daring prison break. Mexican authorities had him in their sights until he made another harrowing escape.

And bad blood? Joe Biden appears to take swipes at Hillary Clinton as the vice president keeps America guessing about his presidential plans. Tonight, Taylor Swift's anthem about soured friendships is making a mark on the Democratic race.

We want to welcome our viewers in the United States and around the world. I'm Wolf Blitzer. You're in THE SITUATION ROOM.

Tonight, we're breaking through the secrecy surrounding a just- reached deal to prevent Russian warplanes from colliding with U.S. military jets over the battlefields of Syria. CNN is learning about surprising gaffes in the agreement that are raising new questions about whether it will actually make U.S. pilots any safer.

Also this hour, we have dramatic new details about the latest escape of one of the world's most wanted and dangerous fugitives. CNN has learned that the drug lord known as El Chapo was spotted by Mexican special forces, but managed to dodge capture after falling off a cliff.

I will ask Congressman Peter King about those stories and more. He's a top member of both the Intelligence and Homeland Security Committees. And our correspondents and analysts are also standing by as we cover all of the news that's breaking right now.

First, let's go to our Pentagon correspondent, Barbara Starr.

Barbara, the U.S. agreed to Russia's demand to keep the details of this new agreement under wraps. What's going on over here? Because it's obviously very sensitive.

BARBARA STARR, CNN PENTAGON CORRESPONDENT: Wolf, three rounds of negotiations with the Russian military and the Pentagon. Today, the Pentagon announcing the agreement has been reached, but also saying that the U.S. agreed to the Russian demand not to make any of the details public.

What we are learning tonight is there is a good deal of vagueness in this agreement, perhaps. There are, we are told by U.S. officials, no specific details about how far away Russian and U.S. warplanes must remain over the very dangerous skies of Syria.

This is all about keeping an accident from happening. U.S. officials say they don't think the Russians have hostile intent, they do not anticipate some attempted shoot-down or some catastrophic event like that, but the big worry, a catastrophic event like an air accident, because the Russians in the last several days have flown very close over those skies of Syria to U.S. warplanes, in one instance about 500 feet and another instance about 1,500 feet.

When you are flying fast at high altitudes and you are that close, there is very little margin for error. That is the concern, we are told by U.S. military officials, that there not be an accident. So, this secret agreement, apparently, by all accounts, actually has very few details in it.

If there is an incident, if a U.S. pilot perhaps feels threatened, they call to their command center in the Middle East. That Middle East command center calls to the Russians in Syria, and hopefully, there would be enough time to work it all out -- Wolf.

BLITZER: Key word, hopefully.

All right, Barbara, thank you.

Let's go to the escalating violence now between Israelis and Palestinians as new attacks played out today. The United Nations secretary-general, Ban Ki-Moon, he was in the region pleading for calm.

CNN's Oren Liebermann is joining us live from Jerusalem right now.

Oren, are there new diplomatic moves under way right now, because so far, the bloodshed continues?

OREN LIEBERMANN, CNN CORRESPONDENT: International efforts now focusing on Israelis and Palestinians, trying to bring these two sides together. Those efforts not having any effect, at least not today, where we have seen three attacks.

The violence now no longer in Jerusalem, which has a tense quiet, now shifting to the West Bank city of Hebron.

(BEGIN VIDEOTAPE) LIEBERMANN (voice-over): Israeli soldiers on the scene of

another attack in the West Bank, this one near the city of Hebron, now becoming the focal point of violence.

[18:05:07]

The Israeli military says a Palestinian driver rammed his car into a bus station, hitting an Israeli soldier and a civilian, forces on the scene shooting and killing the alleged attacker. Earlier in the day, a hit-and-run that left an Israeli man dead. Emergency services say the Israeli was driving when Palestinians threw rocks at his car. AP photos show the Israeli emerging from his car, wielding a wooden club in the middle of the street just moments before he was hit and killed. The driver is under investigation, the IDF telling CNN it's uncertain it was intentional.

Meanwhile, clashes breaking out in Bethlehem and Ramallah in the West Bank, as Palestinian protesters face off against Israeli forces. In Bitunia, southwest of Ramallah, Israel arresting Hamas leader Hassan Yusef, the highest-profile arrest so far in this latest round of violence, the IDF saying Yusef was inciting terrorism and encouraging attacks against Israelis.

On the diplomatic front, U.N. Secretary-General Ban Ki-Moon visiting the region to try to ease the tensions and stop the violence.

BENJAMIN NETANYAHU, ISRAELI PRIME MINISTER: It's not the settlements. It's not the peace process. It's the desire to destroy the state of Israel, pure and simple. President Abbas, unfortunately, has been fanning the flames. He said on September 16, just a few days ago, that he welcomes "every drop of blood spilled in Jerusalem."

LIEBERMANN: But Palestinian leaders blame Israel for that incitement and for using too much force in trying to maintain security. The international community trying to play a bigger role to calm tensions that show no signs of easing.

(END VIDEOTAPE)

LIEBERMANN: Now it will be U.S. Secretary of State John Kerry stepping in, trying to bring these two sides together, try to create some dialogue. Right now, these two sides, Israelis and Palestinians, not talking to each other. He's scheduled to meet Prime Minister Netanyahu. He's scheduled to meet Palestinian President Mahmoud Abbas.

Wolf, will he have any more success than Ban Ki-Moon? I'm not sure anybody right now here is hopeful.

BLITZER: Oren Liebermann in Jerusalem for us, thank you.

Here in the United States, a new leak of the CIA director's personal information could happen at any time. Alleged cyber- criminals are threatening to go public with details from John Brennan's e-mails. They're also revealing how they apparently hacked into Brennan's private account, opening up in an interview with CNN.

Our justice reporter, Evan Perez, has been watching this story. He's got the latest on the unfolding developments.

They're still communicating today. Is there any indication law enforcement authorities are getting closer to finding out who these individuals are?

EVAN PEREZ, CNN JUSTICE CORRESPONDENT: Wolf, they're daring the FBI to come and get them. They're communicating with us, with other news organizations. They have told "The New York Post" that they're going to post information from a top official at the Pentagon. They have also told similar things to other news organizations about other officials. We have yet to see, actually, any additional sensitive information being released, other than things that they have sent us to prove that they have what they have.

BLITZER: CNN's Laurie Segall actually spoke with one of these alleged hackers. I want to play you a clip from that conversation.

(BEGIN VIDEO CLIP)

UNIDENTIFIED MALE: Well, we had most of his personal information, like his name, address, phone number, Social Security number, and other things.

And we socially engineered, we like manipulated AOL to like do the password reset on the account. It was that easy that I could have done it with one hand.

(END VIDEO CLIP)

BLITZER: All right, so, you have been checking in with law enforcement authorities. As far as you know, they haven't identified or apprehended this individual on this recording.

PEREZ: Right. They do believe that this is not any state actor, this is not the Russians or the Chinese. They don't believe it's a foreign intelligence service that did this.

They do believe it's a group of, perhaps, young kids who have nothing better to do with their time, Wolf. I mean, this is something that's so unsophisticated that it has defeated, really, all of the sophisticated things we do to protect our information. These are people who simply called up and pranked people using little bits of information. That's what's scary about this.

Little bits of information that we all have about ourselves on the Internet can be used to put together enough to trick people into providing this kind of access.

BLITZER: Because it clearly was not, apparently, a very sophisticated operation. So, what are they doing to prevent down the road other top officials having their personal private e-mail accounts hacked?

PEREZ: There's really very little they can do.

One of the things that I know -- I talked to officials today who said, well, you know, you can have the security from the various agencies come to your house and check the security of your networks. That doesn't work in this case. This is simply some kid calling up Verizon or some other service provider and tricking them into providing access to your private accounts. That, you really can't really defend against.

BLITZER: All right, Evan, thanks very much.

Joining us now is a top member of the House Intelligence and Homeland Security Committees, Republican Congressman Peter King of New York.

[18:10:00]

Congressman, thanks for joining us.

(CROSSTALK)

BLITZER: Let me get your response to this. The only information we know about this mysterious actor is what he's actually told us, told us here at CNN.

Are you concerned that this might not necessarily be some punk out there, some American teenager smoking pot, but could be a cover for some more nefarious attack by a government?

REP. PETER KING (R), NEW YORK: Wolf, we have to run everything down.

It's bad enough if it is just some young punk, as you said, but, again, we can't rule anything else out. And I can assure you that the FBI right now is doing everything it possibly can. But, again, it would be a big mistake to rule anything out.

And, also, I think there are several lessons from this. One, I think government officials have to learn not to put anything at all on their personal account or private account that in any way involves the government, any type of classified information, but not even classified information. Anything at all involving the government should not be put on a personal account.

It's just -- you know, it's too dangerous. Secondly, I hope, in fact, I know that the FBI will be doing all it can to...

BLITZER: Go ahead.

KING: It will do all it can to find and prosecute to the fullest extent these hackers.

This is not a joke. This is serious business. This is the real deal. And so for anyone to think this is somehow lighthearted or humorous, no, this is serious business. And the example has to be made, if and when they are found. These individuals will be prosecuted and, if found guilty, should get, to me, a maximum sentence on this. This is serious business.

BLITZER: All right, Congressman, I want to stand by. We have a lot more to discuss what's going on, much more with Peter King when we come back.

(COMMERCIAL BREAK)

[18:16:45]

BLITZER: We're back with Congressman Peter King of New York. He's a member of the House Intelligence and Homeland Security Committees.

Congressman, are you going to ask that John Brennan, the CIA director, testify before your committee as a result of the hacking of his personal e-mail account?

KING: Well, that would be up to our chairman, Devin Nunes, but I would certainly urge that we certainly have Director Brennan come in and give us a full scope and an explanation as to what happened, because this goes far beyond John Brennan.

It goes, could any secrets have been compromised, and what steps are going to be taken in the future to prevent this from happening? And, also, is there anyone else at the CIA who's using, you know, private e-mail, and whether or not any government documents go on those personal accounts?

BLITZER: Are you using private e-mail?

KING: I use it for totally nongovernmental. I use it for personal and political.

BLITZER: For personal and political reasons, because you can't use government e-mail for political reasons, fund-raising, stuff like that.

You saw the reports from Barbara Starr at the Pentagon, Oren Liebermann in Jerusalem. It looks like that whole region now is on fire, the violence erupting not only in Syria, elsewhere in the region, Afghanistan, Iraq, Libya, but now what's going on in Israel and the West Bank.

It looks like this region has become a tinderbox just waiting to explode. Is that going too far?

KING: I think you're pretty close to the mark, Wolf, and I think part of the reason -- I'm trying not to be partisan here -- but the fact is, as the U.S. has vacillated, as the U.S. has withdrawn its influence, that vacuum is being filled.

It's being filled by the Russians in Syria. I believe it encourages the Palestinians, who see wavering support for Israel, and certainly the animosity between President Obama and Prime Minister Netanyahu. So, yes, I say indecisive policies by the U.S. are causing others to move to take advantage of it, to fill those vacuums, and the violence we're seeing now, not all of it, but a good part of it, is attributable to that.

BLITZER: Let's talk about politics a little bit. Donald Trump, as you know, he has been in this battle with Jeb Bush about whether President George W. Bush could have done more in the months leading up to 9/11 to prevent that horrible terror attack.

Donald Trump says, yes, he could have done more. Jeb Bush says that Donald Trump is completely wrong. I know you like Donald Trump, but in this particular case, you say he sounds like Michael Moore. But there have been indications, there have been reports saying more could have been done. You have seen the 9/11 Commission reports, for example.

KING: Wolf, I almost entirely disagree with that.

Yes, there were reports that al Qaeda may try to attack the United States. That went back to 1998, 1999, 2000. But President Bush was briefed extensively, and every one of those briefings, including the August 6 briefing from Mike Morell, saying that there was no indication whatsoever that there was any planned attack against the United States.

The attacks they were concerned about were in Europe, and the president specifically asked, is there any evidence at all of a -- any specific evidence at all of an attack against the United States? The answer was no.

In his memoirs, George Tenet, the director of the CIA, said they had no knowledge at all, no intelligence, no information at all that an attack was being planned against the United States. So, yes, it was a general warning? Yes. And that's why the president asked to be briefed. That's why the president asked for a briefing on August 6 on his ranch in Texas.

[18:20:02]

If there was real fear or real threat of an attack coming, wouldn't George Tenet be going to the Oval Office? Wouldn't the CIA be going to the Oval Office? The fact is, they did not because they did not have the intelligence.

And after 9/11, it was President Bush who set up the counterterrorism infrastructure, which has prevented any major attack against the homeland since September 11. But Donald Trump is wrong. He's really echoing Michael Moore, and it's no wonder that so many Democrats are jumping on board, because, really, Donald Trump is sounding more like a very liberal Democrat than a Republican, and he's really distorting history.

I think it's all because Jeb Bush got so much applause at the last debate when he said that his brother had kept the country safe. BLITZER: But, Congressman King, with all due respect, some

analysts who are not Michael Moore, like our own Peter Beinart, Peter Bergen, they say Trump has a point. They say Trump in this particular case -- they both say they don't agree with him on a lot of other stuff, but they say he's right.

And they refer to the presidential daily briefing of August 6, 2001. The headline was "Bin Laden Determined to Strike in U.S., and then it said, "FBI information since 1998 indicates patterns of suspicious activity in this country consistent with preparations for hijackings or other types of attacks, including recent surveillance of federal buildings in New York, in New York."

KING: Absolutely. Right.

BLITZER: And at the time, Richard Clarke, who was the top counterterrorism adviser to the president, said he begged for meetings, for Cabinet-level meetings, he wanted to get more done, and Condoleezza Rice and the president basically put him off, and he was asking...

KING: No.

BLITZER: ... for more to be done. If you read the book by Richard Clarke, that's what he said

KING: I have read Richard Clarke's book, and it seems to me as it's someone who was squeezed out of power and was jealous and was angry about it.

I think Beinart and Bergen -- I respect the both of them. They're wrong here. At this August 6 briefing, they specifically said there was no evidence of an attack now being planned against the U.S. That's why the president asked for the briefing.

Obviously, they knew that al Qaeda wanted to attack the U.S. and that's why the president said, is there a threat of it now? Is everything being done? He was told that there was no threat to the U.S.

(CROSSTALK)

BLITZER: Well, there's another point -- there's another point, Congressman, that Donald Trump makes. And people who know what was going on in those months leading up to 9/11 say he's got a good point, that there really wasn't -- and the 9/11 Commission report concluded there wasn't really a good dialogue with the various branches of the U.S. government.

The FBI was not coordinating with the CIA. They were not coordinating with the NSA. They were not coordinating with the National Security Council. Only after 9/11 did they start working together. And what Trump says, it's the president, the buck stops with him. Why weren't these national security agencies working together to find these terrorists in the United States?

KING: Well, first of all, there was a wall set up between the CIA and the FBI which began during the Clinton administration.

Secondly, the president was eight months into office. This was a system which was intact for a good 10 or 15 years before that.

So, to blame President Bush for something that was in place when he came into office and when the head of the CIA, who, again, is the leading intelligence person in the country, when he tells the president and his memoirs specifically says that there was no intelligence regarding any threats, to me, to be blaming President Bush for that is totally wrong.

I mean, that is totally misguided. It was after 9/11 that the president did reform all that and set in the counterterrorism infrastructure. And we want to start pointing fingers, we could certainly go back into the Clinton administration.

But to be eight months into office and to have inherited a system and to say that that system didn't work and to blame President Bush for that, the fact is, he was the one who was going to the CIA. He was the one who asked for the briefing from Mike Morell in August, August 6, at his ranch in Texas, and Morell in his memoirs and Tenet in his memoirs both say that they told the president there was no evidence at all of any specific attack against the United States, no intelligence. That's the reality.

Meanwhile, we're getting new information right now about the manhunt for a notorious Mexican drug lord who broke out of prison.

I want to bring back CNN's Brian Todd.

Brian, you have new details about El Chapo's latest escape. What are you learning?

BRIAN TODD, CNN CORRESPONDENT: We do, Wolf, new information coming in tonight about El Chapo's encounter with Mexican special forces in recent days.

A source tells us they had a visual glimpse of him, there was a harrowing foot chase through the mountains and a narrow escape.

(BEGIN VIDEOTAPE)

TODD (voice-over): Sources say the fugitive kingpin of the Sinaloa drug cartel, Joaquin "El Chapo" Guzman, was nearly captured in a scene taken straight from the movie "The Fugitive." A Mexican official with knowledge of the manhunt telling CNN

Mexican special forces had spotted the ruthless drug lord earlier this month near the town of Cosala in the Mexican mountains. Guzman was with a child, a young girl, possibly his daughter, the source says, and authorities were reluctant to close in and start a firefight.

Later, when El Chapo was spotted without the child, Mexican marines gave chase. That's when El Chapo either fell or a jumped off small cliff, injuring his face and possibly breaking his leg. At that point, the official says, Guzman's bodyguards rushed to the bottom of the cliff, carried him out and got away through the dense forest.

[18:25:05]

CARL PIKE, FORMER DEA SPECIAL AGENT: They have him pinned in, if you will, right in his area, his backyard.

TODD: One source says Mexican marines weren't able to catch El Chapo at that moment because they were on foot as well. CNN has also learned, three days before that chase, the drug kingpin known for killing thousands of people was spotted in a nearby town on a motorcycle and in a Ferrari with his sons.

Weeks earlier, one son allegedly tweeted this photo, supposedly showing El Chapo brazenly eating at a restaurant. Tonight, however, he may no longer be as bold because of his injuries falling from that cliff.

PIKE: This involves bringing in people that weren't in the normal ring. So, now they have got to find a medical person or a nurse or someone like that that can actually tend to his injuries, and it slows him down, puts him in one particular spot that he wasn't planning on being in before.

TODD: El Chapo is known as a master of high-stakes escapes. He broke out of a high-security Mexican prison in July through this elaborate tunnel. Previously, he eluded police through a trap door hidden under his bathtub. Authorities could be tracking him through his wife, Emma Coronel, a former beauty queen believed to be seen in these photos posted online.

DUNCAN WOOD, WOODROW WILSON CENTER: I would imagine that U.S. authorities, intelligence services and Mexican authorities are tracking her very, very closely, and they have good ways of doing that. So, I would have thought that it's in most likelihood that they are separate for the time being.

(END VIDEOTAPE)

TODD: And even though authorities may be closing the ring around El Chapo, officials caution, do not discount the network of support he has in his home state, in his hometown here, Badiraguato, Tamazula nearby, and Cosala, where that encounter occurred.

Residents here, we're told, consider El Chapo a Robin Hood figure. He's built roads and schools for them. In return, analysts say, if residents there see anything out of the ordinary anywhere in this region, if they see a helicopter, vehicles, people they haven't seen before, they will call El Chapo immediately and tip him off -- Wolf.

BLITZER: All right, Brian Todd, thanks very much.

Just ahead, Osama bin Laden and presidential politics. Is Joe Biden trying to rewrite history as the guessing game over his 2016 plans continues?

And mixed signals from Donald Trump as he wages a war of words over 9/11 and rides high in the polls.

(COMMERCIAL BREAK)

BLITZER: Joe Biden is sounding a lot like a presidential candidate as the vice president faces growing pressure to announce his 2016 plans one way or the other.

[18:32:00] Our senior Washington correspondent, Jeff Zeleny, has been working this story. What are you finding out?

JEFF ZELENY, CNN SENIOR WASHINGTON CORRESPONDENT: Well, Wolf, I can tell you, it sure sounds like he is leaning in that direction. Everyone we talk to says they're left with the impression that he's definitely running.

But the vice president went to great lengths today that shows that he is the president's top adviser, a confidant above all other. If he runs, he knows that he would need that Obama coalition of supporters. That's why he seems so eager to show that he's different from that other Democrat who's still the overwhelming frontrunner in the presidential race.

(BEGIN VIDEOTAPE)

JOE BIDEN, VICE PRESIDENT OF THE UNITED STATES: Hey, folks, how are you?

ZELENY (voice-over): Joe Biden spent the day reminding people he's one heartbeat away from the presidency.

BIDEN: The best decision of my political career was to join the president.

BIDEN: Everybody went around the room, and there were only two people who were definitive and were absolutely certain. Leon Panetta said, "Go," and Bob Gates, who's already publicly said this, said, "Don't go."

ZELENY: Old disagreements from the situation room could flare up in a potential Democratic presidential race. BIDEN: As we walked out of the room and walked upstairs, I said

-- I told them my opinion, that I thought he should go, but follow his own instincts.

ZELENY: He's trying to clear up any criticism from his well- known opposition to the bin Laden raid, also making clear he had the last word with the president, not Secretary of State Hillary Clinton, who's long said she advised the president to authorize the high-stakes raid.

HILLARY CLINTON (D), PRESIDENTIAL CANDIDATE: I was one who recommended to the president that he go ahead, and his advisers were split, because it was a very risky operation.

BIDEN: So help me God.

ZELENY: Biden didn't stop there. He said he had a hand in every decision, even choosing Clinton as secretary of state.

BIDEN: The president at the outset said, "You have veto right on anybody in this cabinet. If you think we should not, move." And sure enough, he asked my opinion on every cabinet member, and we were in total agreement.

ZELENY: For Biden, time is running short. He has nine days to qualify for the ballot in Georgia, followed by deadlines in Alabama and Texas. Even his new polls show Biden in a distant third, and more Democrats say he shouldn't run. His campaign in waiting roars on.

BIDEN: That's the healthy part...

ZELENY: He said again today he doesn't believe Republicans are always the bad guys.

BIDEN: I don't think my chief enemy is the Republican Party. They're -- you know, this is a matter of, you know, making things work.

ZELENY: A not-so-subtle jab at this moment from last week's Democratic debate, when Hillary Clinton was asked to name her enemies.

CLINTON: Well, in addition to the NRA, the health insurance companies, the drug companies, the Iranians, probably the Republicans.

(END VIDEOTAPE)

ZELENY: Of course, Biden and Clinton agree on many things, but their styles are different. Biden believes he is more electable because of this unscripted authenticity. But if he decides to get into the race, he will start well behind. One of his friends said today, Wolf, he can't let this go on much longer.

[18:35:05] BLITZER: All right, Jeff, I want you to stand by. I want to bring in Rebecca Berg. She's the national political reporter for Real Clear Politics. Our chief political correspondent, Dana Bash. And Jamelle Bouie, chief political correspondent for Slate. Dana, was today sort of a preview of what we could expect if --

if -- Joe Biden decides to run for president?

DANA BASH, CNN CHIEF POLITICAL CORRESPONDENT: It certainly sounded like a test drive, there's no question about it.

And just to echo what you were just saying about what you heard from one of his friends, I mean, I've been hearing from Democrats inside the administration, those who have long loved Joe Biden, saying, enough already, just get with it. There's brewing frustration that this has just been going on too long and that it's sort of taking away from the discussion of other things that, never mind the candidates on the 2016 campaign trail want to talk about, but the Obama administration wants to talk about.

So, there's frustration. I just want to borrow a line from one of my favorite Shonda Rhimes programs, which is, there's a planet called passive-aggressiva, and Joe Biden is its king.

BLITZER: And some Democrats say that, you know, he could be, if he runs for the presidency, he could be his own worst enemy, given the history that he has just sort of speaking, shooting from the hip.

JAMELLE BOUIE, CHIEF POLITICAL CORRESPONDENT, "SLATE": Right now, Joe Biden's authenticity and unscriptedness is fun. As soon as he's a serious presidential candidate, it becomes something to be scrutinized.

Every little thing he does, from the odd touching of women to sort of his comments and remarks, becomes grist for the mill. And my view on this is that Joe Biden actually has a chance right now to retire in a great place, beloved vice president. But if he jumps into the race, everything about his behavior and his ticks and his past record, from the war on drugs and the crime bill to his foreign policy decisions and choices becomes, you know, an open field for Clinton, for whoever.

BLITZER: But this is really his last chance, Jeff, to be president of the United States, a position he's wanted for decades. He's run twice before. He did not do well either time.

But we did some research, by the way. Take a look at sitting vice presidents who have actually become president of the United States. Pretty small group, if you take a look at the sitting vice presidents who eventually became president of the United States, were elected president of the United States. Others became president after a president was assassinated, but these are elected presidents. So, there aren't a whole lot.

ZELENY: Incredibly, incredibly small group. I mean, look, he -- one of his challenges here is that, what lane is he going to run in? Is he going to run to the left of Bernie Sanders? No, that's not who he is. Is he going to run to the right of Hillary Clinton? Probably not either.

So, there are -- when you really start to think about this, there are some issues. That's why this has been taking so long.

His heart wants to do it. He wants to be president. He wants to run for president. But practically speaking, it's a little bit more difficult.

And Democrats overall -- I did some, since it's our history lesson tonight -- have only twice succeed -- if a Democrat is in office for two terms, only two times has the party won another term after that. So, it is very, very, very difficult to do this.

But look, he could say he's running as a one-term. He's trying to build this Obama coalition, if he decides to run.

BLITZER: Al Gore came close in 2000...

ZELENY: He did come very close.

BLITZER: ... but it was.

BASH: If you ask him, he won.

BLITZER: Yes. He had more popular votes but not enough electoral votes after the Supreme Court ruled what it did.

Rebecca, take a look at the -- this question that was asked in this NBC News/"Wall Street Journal" poll. Thirty-eight percent of Democrats don't want Biden to run. Thirty percent of them do want the vice president to run. So he's got a lot of work to do, if he decides to run.

REBECCA BERG, REAL CLEAR POLITICS: He does. This is one of the big challenges for Joe Biden and one of the reasons that many Democrats are urging him not to run, because we're not seeing this massive groundswell for Joe Biden in the Democratic Party.

There are some people who would be happy if he ran. There were some people who would certainly support him if he ran, but there's no clamoring for him to run. There's no empty space, necessarily, that he would fill in this field or be able to fill. And so, that's part of his calculation right now: is there a place for him and is there any energy behind his bid, if he does get in?

BLITZER: In all the national polls, he's still No. 3 behind Hillary Clinton, Bernie Sanders. He's got a lot of work to do, if -- if he decides to run. He hasn't announced, but maybe we'll hear from him fairly soon.

Just ahead, has Donald Trump done a foreign policy flip-flop? And if he has, will his supporters even care?

And a struggling presidential candidate venting his frustration with his fellow Democrats in song.

(BEGIN VIDEO CLIP)

MARTIN O'MALLEY (D), PRESIDENTIAL CANDIDATE (singing): 'Cause, baby, now we got bad blood. You know it used to be mad love. So take a look at what you've done that baby now we've got bad blood. Hey!

(END VIDEO CLIP)

[18:44:24] BLITZER: We're back with our political team, and there's now fresh evidence that just two candidates are dominating the crowded Republican presidential race.

Our new CNN/ORC nationwide poll shows Donald Trump at the top of the pack with 27 percent support. His closest rival, Dr. Ben Carson, has 22 percent. There's a huge drop-off after that, with Jeb Bush and Marco Rubio tied with 8 percent. Take a look.

Farther down in the field, Carly Fiorina, who had soared after her early debate performances, now is just 4 -- 4 percent support.

Our chief political correspondent, Dana Bash, is covering the Republican race for us. Trump's numbers, they're still very, very strong.

BASH: They are very strong, and it's not just that he's got support. It's that the supporters he has are very excited about him. They're very enthusiastic about him. And that actually is critically important, because that means that they're more likely to actually go out and cast their votes in these early contest states. But today, Trump stumbled a bit on CNN about the war in

Afghanistan.

Here's what he said on CNN's "NEW DAY" this morning.

(BEGIN VIDEO CLIP)

DONALD TRUMP (R), PRESIDENTIAL CANDIDATE (via telephone): We were safe in a sense, but we went into Iraq, which was a disaster decision, just a disastrous decision. Not Afghanistan, because that's probably where we should have gone in the first place.

(END VIDEO CLIP)

BASH: So, today he said he supports the war in Afghanistan, or did back then, but just two weeks ago on the very same CNN program, he said he opposed it.

(BEGIN VIDEO CLIP)

TRUMP: We made a terrible mistake getting involved there in the first place. We had real brilliant thinkers that didn't know what the hell they were doing.

(END VIDEO CLIP)

BASH: Now, our CNN colleague Alisyn Camerota immediately reminded Trump of that, and he denied flip-flopping. He said Afghanistan is a, quote, "different kettle" from Iraq, saying Pakistan is next to Afghanistan. That country has nuclear weapons. So, it's if he was, you know, kind of -- trying to explain his position now, but there's no question that he said something different two weeks ago.

As far as Jeb Bush and his campaign are concerned, that this is exhibit "A" of what they've been trying to push for the past five days or so, that Donald Trump is not ready for prime time on foreign policy. Not just that, it's they're trying to paint him as liberal, even akin to the liberal filmmaker Michael Moore.

WOLF BLITZER, CNN ANCHOR: Yes, and they're going further than that. But, Jeff, for his supporters among Republicans, it doesn't really seem to matter, does it?

JEFF ZELENY, CNN SENIOR WASHINGTON CORRESPONDENT: It hasn't up until this point. I mean, we could string together a series of examples. Remember that Hugh Hewitt radio interview before the CNN presidential debate, he was unable to sort of identify, you know, things right geographically and leaders. That didn't hurt him at all. He's still the leader in the polls.

But what's happening now is I feel like it's a different moment. I know we've said this before, but there's a sense of, if not panic, urgent concern setting in among Republicans. Keep your eye on other super PACs, like the Bush super PAC and others that are really going to try and remind Republicans that he may not be ready for prime time. We'll see.

But he has defied all types of gravity things before. I have no reason to believe he wouldn't survive something like this in Afghanistan as well.

BLITZER: But there's no doubt, Jamelle, that over these past three or four months since he got into the race, when he attacks, when he is attacked and he attacks back, the guy, or the woman in Carly Fiorina's case, that is attacked usually lose.

JAMELLE BOUIE, CHIEF POLITICAL CORRESPONDENT, SLATE: That's right. And maybe -- maybe it takes a while. There's a little back and forth. You know, Fiorina had her comeback and then she's pretty much plunged in the polls. And this is what we've seen with Jeb Bush. I see no reason to expect this will be any different, even if it's coming from super PACs.

For whatever reason, Trump seems to be invulnerable to attacks from his rivals, which is very unusual, and we'll see how it plays out.

BLITZER: I'm wondering how he's going to respond, Rebecca, to the Jeb Bush op-ed article that was just posted, and I'll read you a line from it.

"Let's be clear," this is Jeb Bush, "Donald Trump simply doesn't know what he's talking about. And his bluster overcompensates for his shocking lack of knowledge on the complex national security challenges that will confront the next president of the United States." That's the op-ed that he posted on "National Review".

You know, he's really going after Donald Trump, but Donald Trump, I suspect, is going to fire right back.

REBECCA BERG, NATIONAL POLITICAL REPORTER, REAL CLEAR POLITICS: I mean, what we've seen to this point, when Jeb Bush tries to get in an argument with Donald Trump, or when he tries to put a dent in his lead, is that Donald Trump has ended up winning many of these arguments. And the problem for Republicans, really, Wolf, is that right now, Jeb Bush is the only Republican candidate who's consistently taking on Donald Trump.

And to Jeff's point, there really is a growing urgency in the Republican Party. I spoke with a Republican, senior Republican today, who said the Republican campaigns have about 90 days, if that, to take Trump out, or else he is winning the nomination.

BASH: The key thing, I think, is -- and I talked to a lot of Republicans who just are kind of resigned to this notion -- is that if you look at Donald Trump's support, it is the highest right now, and he's been there for months, but it's in a field of 11 people, that it might be the case that you're going to have to get one alternative to Donald Trump, many, many others are going to have to drop out to see a real challenge to him, because right now, all the others are splitting the vote.

BLITZER: Is there a Republican, Jamelle, who can fight back and succeed against Donald Trump?

BOUIE: I don't know. Even if you take probably one of the most gifted people in the field, Marco Rubio, and give him all the support of Jeb Bush, of John Kasich, of Chris Christie, of everyone kind of in the mainstream, it doesn't come close to where Trump is and it certainly doesn't come close to Trump with Carson and Ted Cruz combined. I think it's much more likely that Trump falls away and Carson falls away and someone like Cruz takes his support than the reverse.

ZELENY: We'll see if history is the same. But every cycle, come November, as November comes into December, when it comes time to pick a president, if you will, things have changed in other early states. We don't know if it will this time, but historically, it has. So, that's one thing to keep an eye on.

BERG: But we have heard the same thing from Republicans, that after Labor Day, people would start to look at this race more seriously.

[18:50:03] ZELENY: That's true.

BERG: And they keep pushing back the deadline, and it never happens.

ZELENY: Every cycle that I covered, this is my fifth presidential campaign, it's changed every time. Herman Cain was still alive and well at this point four years ago. So, it still, some voters are still tuning in and he's defied. He's been superman so far. We'll see if he continues.

BASH: Started covering presidential campaigns when you were 6, right?

ZELENY: Right, I wish.

BLITZER: There is going to be another Republican debate next week. And then there's going to be a few more. So, there are going to be plenty of opportunities for Carly Fiorina, Marco Rubio, some of these other candidates to score points. So, it's not over with by any means.

BASH: No, not at all. Not even close. There's a lot more time and, obviously, we have to take time for people to start paying attention. There still are a lot, as enthusiastic as Donald Trump supporters are, Ben Carson, as well, there are a lot of Republican voters who are still undecided or not fully committed to the person that they tell pollsters they support now.

BLITZER: You suspect there will be a clash between the two front runners, at least according to all the polls, Donald Trump and Ben Carson?

BOUIE: Maybe it would be -- I've tried to imagine what this clash would look like. Ben Carson is not very combative person. He's very sleepy. He's very sort of -- I don't even -- can't think of any other adjective for him. He just kind of moves slowly.

BASH: Low key.

BOUIE: Low key, low key. Low energy candidate.

ZELENY: Well, they had on immigration, we thought that was moment, and it totally fizzled out. They both returned to their sides intentionally, I think.

BASH: Donald Trump was so complementary of Ben Carson on CNN this morning.

BLITZER: He suggested maybe they could be running mates. Stranger things have happened.

BASH: Exactly. Usually when somebody is nipping at his heels, he turns around and shoots. Not doing that with Ben Carson.

BLITZER: All right. Guys, stand by. Don't go too far away.

When we come back, why did Democratic presidential candidate Martin O'Malley take a page out of Taylor Swift's song?

(BEGIN VIDEO CLIP)

(MARTIN O'MALLEY SINGING)

(END VIDEO CLIP)

(COMMERCIAL BREAK)

[18:56:43] BLITZER: Tonight, Democratic presidential candidate Martin O'Malley appears to be sending a musical message to Hillary Clinton and the other Democratic presidential rivals. Listen to O'Malley on "The View" grabbing his guitar, putting his spin on Taylor Swift's latest hit.

(BEGIN VIDEO CLIP)

(MARTIN O'MALLEY SINGING)

(END VIDEO CLIP)

BLITZER: Rebecca, you're smiling. What do you think?

BERG: I think I'll stick with the Ryan Adams' cover, actually, Wolf.

You know, I guess Martin O'Malley is at the point in his campaign where there is nowhere to go but up so, maybe he is hoping to appeal to some of Taylor Swift's vast fan base with this. And, of course, "The View" is a good venue to do something a little bit lighthearted. But for someone who brags a lot about his singing and his guitar playing, that was the not the most impressive performance I've seen.

BOUIE: I would suggest he stick to a different musical genre.

BERG: Or maybe get some backup singers.

BLITZER: He does a bit Irish. I've seen him perform on St. Patrick's Day when he was governor of Maryland, when he was mayor of Baltimore. He's got pretty good stuff on that. This particular song was not necessarily his strongest.

BERG: He's taking the show on the road in Iowa this weekend at the Jefferson Jackson dinner. So --

BLITZER: A lot of people thought he would be doing a lot better than he's actually -- he's really doing not that well in these polls.

BOUIE: You know, on paper, he seems like he'd be exactly the kind of candidate Democrats want an alternative to Hillary Clinton, but didn't want a left wing candidate like Bernie Sanders to go for it. But I think, you know, for whatever reason, he just isn't catching fire, whether that's the fact that Hillary Clinton has really just crowded out the space of modern Democrats. So, much or if there is some deficiency with his campaigning style.

BLITZER: Joe Biden decides to run, does that further undermine Martin O'Malley's chances?

BERG: Absolutely. I mean, Martin O'Malley doesn't have the same national brand that Joe Biden does. If he was looking for any space in the Democratic primary, it was probably in that lane that Joe Biden would choose. So, I don't see much of a future for him if Biden gets in the race or, you know, frankly even if Biden stays out.

BLITZER: Jim Webb dropped out of the Democratic contest, the former Virginia senator. He wasn't doing very well either. BOUIE: He wasn't even campaigning. I mean, that's what was

comical about this. He barely campaigned, barely made any stops in Iowa or New Hampshire. Then just complained that he wasn't getting all the time and attention he thought he deserved. I'm sorry, but if you want that time and attention, you need to campaign.

Tonight, by the way, our justice correspondent Pamela Brown brings you a CNN special report, "The D.C. Mansion Murders". It was a nightmare end to a charmed life. A father, a mother, their son and family housekeeper murdered in cold blood. The gruesome crime scene, the family's mansion in one of D.C.'s most prominent neighborhoods. That's tonight, 9:00 p.m. Eastern, only here on CNN.

Remember, you can always follow us on Twitter, please tweet me @wolfblitzer. You can tweet the show @CNNSitroom. Please be sure to join us right here in THE SITUATION ROOM tomorrow.

Thanks very much for watching. I'm Wolf Blitzer in THE SITUATION ROOM.